// Copyright (C) Kumo inc. and its affiliates.
// Author: Jeff.li lijippy@163.com
// All rights reserved.
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published
// by the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <https://www.gnu.org/licenses/>.
//
/*-------------------------------------------------------------------------
 *
 * pgtime.h
 *	  PostgreSQL internal timezone library
 *
 * Portions Copyright (c) 1996-2017, PostgreSQL Global Development PGGroup
 *
 * IDENTIFICATION
 *	  src/include/pgtime.h
 *
 *-------------------------------------------------------------------------
 */
#pragma once

#include <cstdint>

/*
 * The API of this library is generally similar to the corresponding
 * C library functions, except that we use pg_time_t which (we hope) is
 * 64 bits wide, and which is most definitely signed not unsigned.
 */

typedef int64_t pg_time_t;

struct pg_tm {
    int tm_sec;
    int tm_min;
    int tm_hour;
    int tm_mday;
    int tm_mon; /* origin 1, not 0! */
    int tm_year; /* relative to 1900 */
    int tm_wday;
    int tm_yday;
    int tm_isdst;
    long int tm_gmtoff;
    const char *tm_zone;
};

typedef struct pg_tz pg_tz;
typedef struct pg_tzenum pg_tzenum;

/* Maximum length of a timezone name (not including trailing null) */
#define TZ_STRLEN_MAX 255

/* these functions are in localtime.c */

struct pg_tm *pg_localtime(const pg_time_t *timep, const pg_tz *tz);

struct pg_tm *pg_gmtime(const pg_time_t *timep);

int pg_next_dst_boundary(const pg_time_t *timep,
                         long int *before_gmtoff,
                         int *before_isdst,
                         pg_time_t *boundary,
                         long int *after_gmtoff,
                         int *after_isdst,
                         const pg_tz *tz);

bool pg_interpret_timezone_abbrev(const char *abbrev,
                                  const pg_time_t *timep,
                                  long int *gmtoff,
                                  int *isdst,
                                  const pg_tz *tz);

bool pg_get_timezone_offset(const pg_tz *tz, long int *gmtoff);

const char *pg_get_timezone_name(pg_tz *tz);

bool pg_tz_acceptable(pg_tz *tz);

/* these functions and variables are in pgtz.c */

pg_tz *session_timezone;
pg_tz *log_timezone;

void pg_timezone_initialize(void);

pg_tz *pg_tzset(const char *tzname);

pg_tz *pg_tzset_offset(long gmtoffset);

pg_tzenum *pg_tzenumerate_start(void);

pg_tz *pg_tzenumerate_next(pg_tzenum *dir);

void pg_tzenumerate_end(pg_tzenum *dir);
